GB2157175A

GB2157175A - Tissue cutting instrument

Info

Publication number: GB2157175A
Application number: GB08409545A
Authority: GB
Inventors: Nii Adjeidu Armar
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-04-12
Filing date: 1984-04-12
Publication date: 1985-10-23
Also published as: GB8409545D0

Abstract

An electrically driven cutting instrument for taking a cone biopsy from the cervix includes a driven continuously looped belt having a cutting edge and running on spools located at 4, 7 and along the shaft towards its distal end 5; the belt also rotating throughout 360 DEG about the axis of the shaft so that the cutting edge describes a cone of excision. The base radius of the cone may be adjusted by the arm 10 and the height of the cone by adjustment of the depth fixator (not shown) located towards the distal end 5 of the shaft. <IMAGE>

Description

SPECIFICATION Tissue cutting instrument This invention relates to an electrically powered moving cutting edge for taking tissue biopsies.

The cervical cone biopsy for example, is a common diagnostic procedure and is, in many instances, curative in the management of patients with pre-cancerous changes in the cervix. To date there are three commonly used instruments for obtaining cervical biopsies (small pieces of tissue). They are as follows: 1. Punch hiopsy forceps, which remove small biopsies 2. Surgical scalpel, with which both small biopsies and cone biopsies may be excised and 3. The diathermy "knife", which both excises cervical biopsies and cauterises the remaining tissue.

These are all hand held and manually operated instruments. The results are very variable and there is no accurately reproducible method of performing this gynaecological procedure. A large element of guess work is involved and in particular at the apex of the cone where it is not possible to determine whether unnecessary injury is inflicted on the proximal cervix and in the extreme instance, on the uterine isthmus, when deep large cone biopsies are taken.

This invention affords semi-automated specimen removal because the depth, height and base radius of the cone can be pre-determined and accurately maintained through 360 degrees as necessary. Alternatively, variations in the base radius may be made with simple manipulation of the cutting angle adjustor, as the moving cutting edge revolves within the cervix. Because the procedure can be accurately reproduced, findings at colposcopy, if mapped out clearly by the colposcopist, may be transferred to the cervix of the anaesthetised patient and the procedure carried out with accuracy by a gynaecologist other than the colposcopist.

With the aid of an adequate speculum, the gynaecologist is therefore able to remove the cone biopsy single-handed, and with the knowledge that beyond the cone apex, no soft tissue injury will be inflicted.

The colposcopist may also give specific instructions based on dimensions obtained through use of the planning device (Cone Guide) at the time of colposcopy.

The excised tissue is only subjected to incision and is therefore minimally damaged. It therefore re mains very adequate for histological analysis.

A A specific embodiment of the electrically powered cutting edge will now be described by way of exam ple with reference to the accompanying drawings.

Figure 1 shows the profile of the Electrically powered cutting instrument with the cutting angle head 1.

Figure 2a, 2b and 2c illustrate cutting angle head 1, showing the lateral view, the view from above and the end-on view from the distal end.

Figure 3a, 3b and 3c illustrate cutting angle head 2, showing the same views as in Figures 2a, 2b and 2c.

Figure 4a illustrates the cutting edge adjustors' locking mechanism when cutting angle heads 1 and 2 are in use, and FIGURE 4b shows the adjustors carriage. Figure 4c shows the locking ridge, detached from the carriage.

Figure 5 shows the profile of the Electrically powered cutting instrument with cutting angle head 3 in two positions, A being proximal and B distal.

Figure 6 illustrates cutting angle head 3.

Figure 7a illustrates a cross-section of the cylinder to which the cutting angle adjustor operating arm is attached, showing the locking mechanism with the locking arm extension from the cutting angle head 3 carriage and 7b shows the proximal part of the locking arm extension.

Figure 8a illustrates the transmission principle and Figure 8b, the cutting edge on its drive.

Figure 9 illustrates the passage of the stabilizer cable from the handle of the instrument to the stabi lizer piece.

Figure 10a and 10b illustrate the stabilizer piece in closed and open positions.

Figure 11 shows the clip-on protector.

Figure 12 shows the cone guide.

Details of Figure 1 1. Handle of instrument, housing electric motor 2. Carriage to which operating arm (10) is attached. It locks with the holder of cutting angle (spoolholding) arm (9) 3. Arm of cutting angle spool-holder 4. Spool holder 5. Open end of operating head from which stabilizing piece protrudes 6. Cut-out on side of operating head for removing and replacing cutting edge 7. Bulhous housing for proximal (drive) spool, to which the revolution of the main shaft is transmitted 8. Closed intermediate part of operating head on which locked cutting angle adjustor mechanism travels 9. Carriage for cutting angle adjustor arm 10. Cutting angle adjustor operating arm 11. Extensions from (2), the proximal parts of which are held in a groove in (12) to maintain the radial position of (2) relative to (12) 12. Intermediate shaft base Details of Figures 2a, 2b and 2c 1.Locking ridge on cutting angle arm carriage 2. Locking groove on cutting angle arm carriage 3. Cutting angle arm carriage 4. Base of cutting arm 5. Cutting arm 6. Spool "a" holder 7. Spool"a" 8. Cut-out for changing spool "a" spindle 9. Lonqitudinal ridge on inner aspect of carriage to ensure its synchronous movement with the operating head. There are corresponding grooves on the operating head Details of Figures 3a, 3b and 3c are as for FIGURES 2a, 2b and 2c.

Details of Figures 4a, 4b and 4c 1. Releasing arm of locking ridge 2. Spindle for locking piece 3. Locking ridge, attached to adjustor arm carriage 4. Corresponding locking groove on cutting angle arm carriage 5. Base of cutting angle arm 6. Cutting angle arm 7. Closed part of operating head 8. Cutting angle arm carriage 9. Cutting arm adjustor carriage (The adjustor arm in not shown as, in figure 4a, it is at right angles to the plane of the diagram. See Figure 4c) 10. Locking piece spindle holder 11. Extensions from (9), the proximal part of which are held in a qroove in the intermediate shaft base to maintain its position 12. Cut-out on cutting arm adjustor carriage, housing locking piece Details of Figure 5 1. Stabilizer switch 2. Handle of instrument 3. Cut-out for movement of cutting edge 4. Spool holder on cutting angle head 3 5. Same as (3) 6. Open end of operating head from which stabilizing piece protrudes 7. Cutting angle head carriage 8. Cut-out part of cutting angle head carriage and operating head to enable removal and replacement of cutting edge 9. Cut-out part of intermediate shaft through which adjustor arm passes 10. Adjustor arm 11. Intermediate shaft 12. Operating trigger 13. Insulated cable (Carriage in positions A and B) Details of Figure 6 1. Spindle for spool "a" 2. Spool holder 3. Catch for securing spool holder 4. Carriage for spool holder 5. Cut-out to facilitate replacement of cuttin g edge 6. Locking arm extension from spool holder carriage 7. Pivot on which spool holder moves: This is mounted on a spring Details of Figures 7a and 7b 1. Cross section of cylinder 2. Groove at distal end of cylinder 3. Hooked locking end of arm of cutting angle head 3 4.Open end of cylinder through which operating head passes Details of Figure 8a and 8b 1. Drive shaft 2. Drive shaft bevel 3. Stabilizing bevel gear 4. Spindle 5. Operating head 6. Cutting edge drive bevel gear 7. Bulbous housing. See FIGURE 1, (7) 8. Cutting edge drive 9. Hole in spindle to allow passage of stabilizer cable 10. Cut-out part of housing, to enable replacement of cutting edge 11. Cutting edge 12. Cut-out "eye" in cutting edge 13. Elevation on cutting edge drive 14. Central hole for spindle 15. Cutting edge drive Details of Figure 9 1. Stabilizer cable 2. Opening in spindle to allow passage of cable 3. Cutting-edge drive spindle 4. Distal spool spindle 5. Stabilizer piece 6. Open end of operating head 7. Cut-out on side of operating head for changing cutting edge 8. Distal spool 9.Bulbous housing for transmission mechanism 10. Drive shaft 11. Intermediate part of operating head Details of Figure 10 1. Stabilizer cord 2. Operating head 3. Solid cylindrical piece attached to inner aspect of operating head: this has a conically concave distal end 4. Long arm of stabilizer tooth 5. Open end of operating head 6. Stabilizer tooth Details of Figure 11 1. Protector head base with clips on to operating head 2. Grips on inner aspect of base 3. Protector head Details of Figure 12 1. Handle of Cone Guide 2. Shaft of Cone Guide 3. Carriage for radial arm 4. Radial arm 5. Tapered but blunt tip of Cone Guide Dimensions (operating head) 1. Maximum diameter of operating head 6.0mm 2. Open end of operating head (diameter) 4.5mm 3. Diameter of intermediate shaft 13.0mm 4.Maximum width of cutting edge 2.5mm 5. Distance between cutting edge drive and distal spool 60.0mm 6. Maximum diameter of bulbous housing 16.0mm 7. Tapered end of operating head 7.5mm 8. Maximum distance between cutting edge and operating head 17.5mm 9. Maximum diameter of intermediate shaft base 25.0mm 10. Short markings on operating head 2.5mm 11. Long markings on operating head 5.0mm Dimensions (cone guide) 1. Maximum diameter of shaft 4.5mm 2. Maximum length 120.0mm 3. Length of radial arm 27.0mm 4. Short markings on shaft and radial arm 2.5mm 5. Intermediate markings on shaft and radial arm 5.0mm 6. Long markings on shaft and radial arm 10.00mm N.B. The primary colours may be used to represent the various distances.

Claims

1. An electrically operated movable cutting edge for incising tissue.

2. An electrically operated movable cutting edge for incising tissue in a pre-determined fashion.

3. An electrically operated movable cutting edge which revolves through 360 degrees along its long axis thereby providing a means for excising a cone of tissue of pre-determined height and base radius.

4. An electrically operated cutting edge as claimed in 1, 2 and 3 wherein a means is provided for varying the cone angle and thus the base radius at any point during the 360 degree revolution of the cutting edge within the tissue being biopsied.

5. An electrically operated movable cutting edge as claimed in claims 1,2,3 and 4 wherein a means is provided for stabilising the operating head of the instrument within the tissue from which the biopsy is to be obtained.

6. An electrically operated movable cutting edge as claimed in claim 5 wherein a means is provided for varying the cone height (i.e., depth of placement of the operating head within the tissue).

7. An angled cutting head for cutting a ring or part of a ring of tissue such that the maximum angle attainable between the long axis of the cone and the cut surface may exceed 90 degrees.

8. A cone biopsy' 'guide" for use at colposcopy and if necessary at any time or immediately prior to the surgical undertaking of cone biopsy.

9. A "clip-on" protector for use on the operating head of the electrically operated cutting instrument to protect adjacent tissues from accidental trauma from the redundant part of the cutting edge during its use.

10. An electrically operated movable cutting edge as claimed in Claims 1 to 6 wherein a means is provided for the accurate, reproducible excision of tissue without damage to the tissue beyond the apex of the excised tissue.

11. An electrically operated movable cutting edge, substantially as described herein, with reference to figures 1 to 12 of the accompanying drawings, which facilitates removal of a cone of tissue of variable height and base radius with minimal trauma to the remaining tissue, and at the same time providing a histologically adequate specimen for detailed examination.